One type of malocclusion is a Class III which often times involves a maxillary deficiency. A Class III malocclusion is a condition in which the chin of an individual appears to protrude forwardly a disproportionate amount. Class III malocclusions may be due to excessive mandibular growth and/or maxillary deficiency. One method for treating a Class III malocclusion involving a retracted maxilla is to exert a generally mesially directed force on the bony structures of the lower face by engaging the upper arch of the orthodontic patient. These types of force stimulate bone growth to advance the maxilla mesially and/or orthodontically advance the patient's dentition.
Another type of malocclusion is a Class II malocclusion. A Class II malocclusion exhibits a rearward displaced chin or generally underdeveloped jaw. Particularly in younger patients, this type of malocclusion responds well to generally mesially-directed treatment forces.
The above-noted types of mesially-directed forces are typically applied using what may be characterized as a reverse pull assembly. Known reverse pull assemblies allow for the exertion of the generally mesially-directed force on the patient's upper arch or lower arch by providing a plurality of supports on the patient's facial or head region and by including structure which is outwardly displaced from the patient's face to provide a mounting for elastics or other treatment force generating members. These elastics extend from their mounting on the reverse pull assembly under tension and engage the patient's upper or lower arch. In the case where a rigid arch wire or the like is interconnected with the patient's upper or lower teeth, a pair of elastics are typically used to engage opposite sides of the arch undergoing treatment (e.g,. by engaging hooked appliances indirectly attached to bands on the patient's teeth). The tensioned elastics thereby apply a symmetrical, generally mesially-directed force on the patient's arch undergoing treatment to attempt to achieve the noted objectives, while the corresponding generally distally directed forces are exerted on the patient at the various facial or head supports.